Oct 31
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The Java Language Specification can be found here.
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The Java Language Specification can be found here.
The DBUtil library from Apache provides a set of class for doing a variety of standard database tasks. eg. To make a query becomes as simple as the following, providing the result set as a List of arrays where each list elements contains a row. QueryRunner runner = new QueryRunner(); ArrayListHandler handler = new ArrayListHandler(); List<Object[]> result = runner.query(connection, "SELECT * FROM MyTable WHERE name=?", handler, "Joe Smith"); DbUtils.close(conn);
The Spherical law of cosines gives a pretty accurate result that will be sufficient for most applications. /** lat, longs are in radians */ public static double distance(double lat1, double lon1, double lat2, double lon2) { return R * Math.acos(Math.sin(lat1) * Math.sin(lat2) + Math.cos(lat1) * Math.cos(lat2) * Math.cos(lon1 - lon2)); } private static final double R = 6371.0; // earths mean radius in km |
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